# Tag Info

The key point is to have an acid with such a high $\ce{H+}$ activity that in large extent shifts the below reaction to the left : $$\ce{ HSO4- + H2O <=> SO4^2- + H3O+ } \\ K_\mathrm{a2}=1.0 \cdot 10^{-2}$$ Then activity of sulphate ions from dissolution of $\ce{BaSO4}$ is decreased by the equilibrium reaction and the solubility increases. \begin{...